Q: Can my listing agent sue for additional commission after settlement?

A: Anybody can sue for anything. All it requires is a pen, a piece of paper, and the filing fee ... and, sometimes, a crayon has been substituted for the pen. What you are trying to ask is whether the listing agent can win, and that depends on what your listing agreement says and whether than agreement violates the real estate brokerage code of the jurisdiction or the NAR standards. You should probably show the threatening email or letter to a lawyer.

A: Your listing agent is due a fee or commission based on a contract. If the contract states he/she is entitled to the commission, then they have a right to claim it; if not, then no. Read your contract with the listing agent, or take it to a lawyer to interpret it for you. Demand that the listing agent identify by paragraph, section and quoted provision in the contract their basis for claiming the additional commission.

A: The answer will be discerned from the brokerage/agency agreement, the settlement sheet, and your written communications. If the broker's agreement calls for $X, but the disbursement out of settlement was less than $X, then you might owe he delta.

That is just the beginning of the analysis, as there are issues of timing, forum, equitable and legal defenses, and possible mandatory mediation (often described in both your broker agreement and the contract of sale).